Pale Blue Dot is the name given to this 1990 photo of
Earth taken from
Voyager 1 when its vantage point reached the edge of the
Solar System, a distance of roughly 3.7 billion miles (6 billion kilometres). Earth can be seen as a blueish-white speck approximately halfway down the brown band to the right. The light band over Earth is an artifact of sunlight
scattering in the camera's
lens, resulting from the small angle between Earth and the
Sun.
Carl Sagan came up with the idea of turning the spacecraft around to take a composite image of the Solar System. Six years later, he reflected, "All of human history has happened on that tiny pixel, which is our only home."
Photo credit: NASA/JPL